Blister Microscope, Explore the tine world around you

MICROSCOPE EXPERIMENT 1
The Feather

Find a feather
This vane, or blade section of the feather is the area we will look at. To the naked eye, the blade has two parts: the central stem, called the rachis, and many little side branches, called barbs.

Place feather in Blister Microscope and view with 25x objective
Under the low power (25X) objective of our microscope we can see that the barbs aren’t just simple stems extending from the rachis. In fact, each barb has many little hairy structures extending from it called barbules (pronounced, bar-byools). The barbules perform a critical function for feathers. They extend far enough to overlap with the barbules on the adjacent barbs on each side of the barb to which they are attached. This overlap allows each barbule to become entangled with barbules on other barbs so that air can’t pass easily through them. If they didn’t do this, then the feathers would let air pass through them, and the bird wouldn’t be able to fly as well, and perhaps, not fly at all. While each little barbule is a tiny, weak, little structure, when many of them combine to entangle with other barbules, up and down the length of each barb, they hold the feather together like the threads in our clothes.

View feather with 50x objective.
Under the 50X, and certainly under the 100X objectives we can easily see how the barbules overlap each other and entangle.

And so, it’s in the tiny details of a bird’s feather that allows birds to soar through the air. Some people may say that birds can fly because they have wings, and that is correct. But why do their wings allow them to fly? Because they have feathers. And why do feathers do what they do? Because, as we have learned, they have barbs, and barbules on their barbs.

Tony Mommsen Web Design

MICROSCOPE EXPERIMENT 1 The Feather

MICROSCOPE EXPERIMENT 1
The Feather